mips: move sysmips parser to a separate file

* sysmips.c: New file.
* Makefile.am (strace_SOURCES): Add it.
* system.c: Fix typo in the check for <linux/utsname.h>.
Move inclusions of <linux/utsname.h> and <asm/sysmips.h> to sysmips.c.
[MIPS]: Likewise.
diff --git a/Makefile.am b/Makefile.am
index 38193f2..3c89725 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -53,6 +53,7 @@
 	stream.c	\
 	syscall.c	\
 	sysinfo.c	\
+	sysmips.c	\
 	system.c	\
 	term.c		\
 	time.c		\